Luggage Storage near Brussels?

I am an American student who will be studying at KU Leuven this fall. I'll be travelling around Europe a bit from September 4th through September 15th or so, but I won't be able to carry around all of my luggage.

Could anyone recommend a place to store luggage for 10 or more days? From what I have seen, airports/train stations have a 48 hour storage limit.